In the evolution of hybrid integrated circuits for switching systems and high performance processes as well as other electronic devices one of the most critical system packaging needs is the capability of utilizing effectively high I/O pin-out devices with high speed interconnections. To meet this goal multilayer ceramic hybrid integrated circuits have been developed. However, the currently available multilayer ceramic circuits require a complex manufacturing system and are relatively expensive. Consequently, in order to meet the packaging needs of such hybrid integrated circuits while retaining quality, reliability and performance demands, especially in conjunction with the use of very large scale integrated circuit chips, in a cost competitive package, further improvements are necessary.
To meet this goal, I believe that a multilayer polymer hybrid integrated circuit configuration is one approach to solving the problem. The polymer layer must act as a dielectric material between layers containing thin film circuitry and must meet many other stringent requirements including a high T.sub.g, a high thermal stability and hybrid process compatibility. It would also be preferred if such a polymeric material were photodefinable.